Actively exploitedCVSS 5.1 · MEDIUM

CVE-2015-3246Privilege Escalation in Red Hat libuser

Red Hat libuser contains a race condition vulnerability that allows authenticated local users to corrupt the /etc/passwd file to cause a denial of service or privilege escalation.

View on NVD

Analysis

Esta vulnerabilidad en la librería libuser de sistemas Linux permite a usuarios locales corromper el archivo /etc/passwd para obtener privilegios de root o causar una denegación de servicio. El fallo está en la lista KEV de CISA debido a que se ha detectado su explotación activa. Es especialmente relevante para quienes administran servidores o contenedores basados en Red Hat y distribuciones derivadas.

Relevant roles

LinuxciberseguridadBackendCloud

Severity

Score: 5.1(MEDIUM)

Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

AV: LOCAL

AC: HIGH

PR: NONE

UI: NONE

S: UNCHANGED

C: NONE

I: NONE

A: HIGH

Weakness (CWE): CWE-264CWE-367

CISA KEV

Added to KEV: 2026-08-26

Federal patch deadline: 2026-09-09

Known ransomware use: Unknown

Required action

Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

EPSS

Probability of exploitation (next 30 days): 0.0709 (7.1%)

Percentile: 93.7%

EPSS: 2026-08-26

Affects

redhat:enterprise_linuxopensuse:opensuselibuser_project:libuser

Technical description

libuser before 0.56.13-8 and 0.60 before 0.60-7, as used in the userhelper program in the usermode package, directly modifies /etc/passwd, which allows local users to cause a denial of service (inconsistent file state) by causing an error during the modification. NOTE: this issue can be combined with CVE-2015-3245 to gain privileges.

Published: 8/11/2015, 2:59:07 PM

Last modified: 8/26/2026, 8:29:25 PM

References

How to read this card

Actively exploited

KEV (Known Exploited Vulnerabilities) is CISA's catalog of CVEs confirmed as actively exploited in the real world. If a CVE is on KEV, someone is already using it in attacks.

CVSS 10.0

CVSS 10.0 — máxima severidad teórica. Explotable de forma remota, sin privilegios, con impacto total. Aún no confirmada como explotada en el mundo real, pero parchea ya.

AI-recommended

Un modelo de lenguaje revisó el CVE y consideró que afecta a software ampliamente desplegado o herramientas comunes de desarrollo. Un humano del equipo aprobó la publicación antes de que llegara aquí.

Categorías de impacto que evalúa la IA

widely_deployed_infra — kernel Linux, OpenSSL, glibc, k8s, Docker, nginx, OpenSSH.

popular_dev_tooling — Node.js, Python, Go, React, Next.js, librerías comunes de npm/pip.

common_consumer_software — Chrome, Firefox, Windows, macOS, apps móviles populares.

enterprise_saas — GitHub, GitLab, Atlassian, Salesforce, Cisco, Fortinet, Ivanti.

niche_software — CMS regionales, herramientas de hobby, librerías de poco uso.

not_relevant — firmware específico de proveedor, software descontinuado.

EPSS — EPSS (Exploit Prediction Scoring System) by FIRST.org estimates the probability that a CVE will be exploited in the next 30 days. Range is 0 to 1; very fresh CVEs typically score low until evidence accumulates.